source3/nmbd/nmbd_responserecordsdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    NBT netbios library routines
   4    Copyright (C) Andrew Tridgell 1994-1998
   5    Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   6    Copyright (C) Jeremy Allison 1994-1998
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20
  21 */
  22
  23 #include "includes.h"
  24
  25 int num_response_packets = 0;
  26
  27 /***************************************************************************
  28   Add an expected response record into the list
  29   **************************************************************************/
  30
  31 static void add_response_record(struct subnet_record *subrec,
  32                                 struct response_record *rrec)
  33 {
  34         struct response_record *rrec2;
  35
  36         num_response_packets++; /* count of total number of packets still around */
  37
  38         DEBUG(4,("add_response_record: adding response record id:%hu to subnet %s. num_records:%d\n",
  39                 rrec->response_id, subrec->subnet_name, num_response_packets));
  40
  41         if (!subrec->responselist) {
  42                 subrec->responselist = rrec;
  43                 rrec->prev = NULL;
  44                 rrec->next = NULL;
  45                 return;
  46         }
  47
  48         for (rrec2 = subrec->responselist; rrec2->next; rrec2 = rrec2->next)
  49                 ;
  50
  51         rrec2->next = rrec;
  52         rrec->next = NULL;
  53         rrec->prev = rrec2;
  54 }
  55
  56 /***************************************************************************
  57   Remove an expected response record from the list
  58   **************************************************************************/
  59
  60 void remove_response_record(struct subnet_record *subrec,
  61                                 struct response_record *rrec)
  62 {
  63         if (rrec->prev)
  64                 rrec->prev->next = rrec->next;
  65         if (rrec->next)
  66                 rrec->next->prev = rrec->prev;
  67
  68         if (subrec->responselist == rrec)
  69                 subrec->responselist = rrec->next;
  70
  71         if(rrec->userdata) {
  72                 if(rrec->userdata->free_fn) {
  73                         (*rrec->userdata->free_fn)(rrec->userdata);
  74                 } else {
  75                         ZERO_STRUCTP(rrec->userdata);
  76                         SAFE_FREE(rrec->userdata);
  77                 }
  78         }
  79
  80         /* Ensure we can delete. */
  81         rrec->packet->locked = False;
  82         free_packet(rrec->packet);
  83
  84         ZERO_STRUCTP(rrec);
  85         SAFE_FREE(rrec);
  86
  87         num_response_packets--; /* count of total number of packets still around */
  88 }
  89
  90 /****************************************************************************
  91   Create a response record for an outgoing packet.
  92   **************************************************************************/
  93
  94 struct response_record *make_response_record( struct subnet_record *subrec,
  95                                               struct packet_struct *p,
  96                                               response_function resp_fn,
  97                                               timeout_response_function timeout_fn,
  98                                               success_function success_fn,
  99                                               fail_function fail_fn,
 100                                               struct userdata_struct *userdata)
 101 {
 102         struct response_record *rrec;
 103         struct nmb_packet *nmb = &p->packet.nmb;
 104
 105         if (!(rrec = SMB_MALLOC_P(struct response_record))) {
 106                 DEBUG(0,("make_response_queue_record: malloc fail for response_record.\n"));
 107                 return NULL;
 108         }
 109
 110         memset((char *)rrec, '\0', sizeof(*rrec));
 111
 112         rrec->response_id = nmb->header.name_trn_id;
 113
 114         rrec->resp_fn = resp_fn;
 115         rrec->timeout_fn = timeout_fn;
 116         rrec->success_fn = success_fn;
 117         rrec->fail_fn = fail_fn;
 118
 119         rrec->packet = p;
 120
 121         if(userdata) {
 122                 /* Intelligent userdata. */
 123                 if(userdata->copy_fn) {
 124                         if((rrec->userdata = (*userdata->copy_fn)(userdata)) == NULL) {
 125                                 DEBUG(0,("make_response_queue_record: copy fail for userdata.\n"));
 126                                 ZERO_STRUCTP(rrec);
 127                                 SAFE_FREE(rrec);
 128                                 return NULL;
 129                         }
 130                 } else {
 131                         /* Primitive userdata, do a memcpy. */
 132                         if((rrec->userdata = (struct userdata_struct *)
 133                                         SMB_MALLOC(sizeof(struct userdata_struct)+userdata->userdata_len)) == NULL) {
 134                                 DEBUG(0,("make_response_queue_record: malloc fail for userdata.\n"));
 135                                 ZERO_STRUCTP(rrec);
 136                                 SAFE_FREE(rrec);
 137                                 return NULL;
 138                         }
 139                         rrec->userdata->copy_fn = userdata->copy_fn;
 140                         rrec->userdata->free_fn = userdata->free_fn;
 141                         rrec->userdata->userdata_len = userdata->userdata_len;
 142                         memcpy(rrec->userdata->data, userdata->data, userdata->userdata_len);
 143                 }
 144         } else {
 145                 rrec->userdata = NULL;
 146         }
 147
 148         rrec->num_msgs = 0;
 149
 150         if(!nmb->header.nm_flags.bcast)
 151                 rrec->repeat_interval = 5; /* 5 seconds for unicast packets. */
 152         else
 153                 rrec->repeat_interval = 1; /* XXXX should be in ms */
 154         rrec->repeat_count = 3; /* 3 retries */
 155         rrec->repeat_time = time(NULL) + rrec->repeat_interval; /* initial retry time */
 156
 157         /* This packet is not being processed. */
 158         rrec->in_expiration_processing = False;
 159
 160         /* Lock the packet so we won't lose it while it's on the list. */
 161         p->locked = True;
 162
 163         add_response_record(subrec, rrec);
 164
 165         return rrec;
 166 }
 167
 168 /****************************************************************************
 169   Find a response in a subnet's name query response list.
 170   **************************************************************************/
 171
 172 static struct response_record *find_response_record_on_subnet(
 173                                 struct subnet_record *subrec, uint16 id)
 174 {
 175         struct response_record *rrec = NULL;
 176
 177         for (rrec = subrec->responselist; rrec; rrec = rrec->next) {
 178                 if (rrec->response_id == id) {
 179                         DEBUG(4, ("find_response_record: found response record id = %hu on subnet %s\n",
 180                                 id, subrec->subnet_name));
 181                         break;
 182                 }
 183         }
 184         return rrec;
 185 }
 186
 187 /****************************************************************************
 188   Find a response in any subnet's name query response list.
 189   **************************************************************************/
 190
 191 struct response_record *find_response_record(struct subnet_record **ppsubrec,
 192                                 uint16 id)
 193 {
 194         struct response_record *rrec = NULL;
 195
 196         for ((*ppsubrec) = FIRST_SUBNET; (*ppsubrec);
 197                                 (*ppsubrec) = NEXT_SUBNET_INCLUDING_UNICAST(*ppsubrec)) {
 198                 if((rrec = find_response_record_on_subnet(*ppsubrec, id)) != NULL)
 199                         return rrec;
 200         }
 201
 202         /* There should never be response records on the remote_broadcast subnet.
 203                         Sanity check to ensure this is so. */
 204         if(remote_broadcast_subnet->responselist != NULL) {
 205                 DEBUG(0,("find_response_record: response record found on subnet %s. This should \
 206 never happen !\n", remote_broadcast_subnet->subnet_name));
 207         }
 208
 209         /* Now check the WINS server subnet if it exists. */
 210         if(wins_server_subnet != NULL) {
 211                 *ppsubrec = wins_server_subnet;
 212                 if((rrec = find_response_record_on_subnet(*ppsubrec, id))!= NULL)
 213                         return rrec;
 214         }
 215
 216         DEBUG(3,("find_response_record: response packet id %hu received with no \
 217 matching record.\n", id));
 218
 219         *ppsubrec = NULL;
 220
 221         return NULL;
 222 }
 223
 224 /****************************************************************************
 225   Check if a refresh is queued for a particular name on a particular subnet.
 226   **************************************************************************/
 227
 228 bool is_refresh_already_queued(struct subnet_record *subrec, struct name_record *namerec)
 229 {
 230         struct response_record *rrec = NULL;
 231
 232         for (rrec = subrec->responselist; rrec; rrec = rrec->next) {
 233                 struct packet_struct *p = rrec->packet;
 234                 struct nmb_packet *nmb = &p->packet.nmb;
 235
 236                 if((nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_8) ||
 237                                 (nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_9)) {
 238                         /* Yes it's a queued refresh - check if the name is correct. */
 239                         if(nmb_name_equal(&nmb->question.question_name, &namerec->name))
 240                         return True;
 241                 }
 242         }
 243
 244         return False;
 245 }